Replace all return "..." HTML string literals with native El templates —
removes all \" escapes, converts + interpolations to {expr}/{raw(expr)},
and replaces conditional string concatenation with {#if}/{#else}/{/if}.
No functional changes; output is identical.
- Nav: all section links are absolute (/#section) - fixes about page back-nav
- Nav: add Environment link
- Safety: "I built" not "we built"; crisis hotline announcement; crisis line coming
- Pillars: rename Learns -> Sharpens with opaque copy that doesn't reveal mechanism